High-Spatial-Resolution Quantum Well Intermixing Technique for All-Optical Nano-Device Fabrications

2009 ◽  
Author(s):  
Chee-Wei Lee ◽  
Yicheng Lai ◽  
Yingyan Huang ◽  
Boyang Liu ◽  
Seng-Tiong Ho
Keyword(s):  
Quantum Well ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Quantum Well Intermixing ◽  
All Optical

Optical Diagnostics of Microstructures Fabricated Using Quantum Well Intermixing

1999 ◽  
Vol 607 ◽  
Author(s):  
A. Saher Helmy ◽  
A.C. Bryce ◽  
C.N. Ironside ◽  
J.S. Aitchison ◽  
J.H. Marsh ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Quantum Well ◽  
Spatial Resolution ◽  
Optical Diagnostics ◽  
Complete Suppression ◽  
Quantum Well Intermixing ◽  
Spatially Resolved ◽  
Non Destructive ◽  
Insight Into ◽  
Free Vacancy

AbstractIn this paper we shall discuss techniques for accurate, non-destructive, optical characterisation of structures fabricated using quantum well intermixing (QWI). Spatially resolved photoluminescence and Raman spectroscopy were used to characterise the lateral bandgap profiles produced by impurity free vacancy disordering (IFVD) technology. Different features were used to examine the spatial resolution of the intermixing process. Features include 1:1 gratings as well as isolated stripes. From the measurements, the spatial selectivity of IFVD could be identified, and was found to be ∼4.5 μm, in contrast with the spatial resolution of the process of sputtering induced intermixing, which was found to be ∼2.5 μm. In addition, PL measurements on 1:1 gratings fabricated using IFVD show almost complete suppression of intermixing dielectric cap gratings with periods less than 10 microns. Finally, some insight into the limitations and merits of PL and Raman for the precision characterisation of QWI will be presented.

Characterization of V-Defects in InGaN Single-Quantum-Well Films at Nanometer Level by High Spatial Resolution Cathodoluminescence Spectroscopy

2008 ◽  
Vol 600-603 ◽  
pp. 1305-1308
Author(s):  
Masanobu Yoshikawa ◽  
Masataka Murakami ◽  
Takaya Fujita ◽  
K. Inoue ◽  
K. Matsuda ◽  
...  
Keyword(s):  
Quantum Well ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Spectral Variation ◽  
Single Quantum ◽  
Single Quantum Well ◽  
Cathodoluminescence Spectroscopy

We have measured cathodoluminescence (CL) spectra in the vicinity of V-defects in InGaN single-quantum-well(SQW) films at nanometer level, using newly developed CL apparatus (SE-SEM-CL). From spectroscopic CL measurement, it has been found that the spectra change dramatically in the vicinity of V-defects in the region of £50nm. The SE-SEM-CL has a potential to detect the CL spectral variation at spatial resolution with £50nm.

Quantum Well Intermixing in Gain As/Gainasp and Gaas/Algaas Structures Using Pulsed Laser Irradiation

1996 ◽  
Vol 450 ◽  
Author(s):  
A. C. Bryce ◽  
R. M. De La Rue ◽  
J. H. Marsh ◽  
B. S. Ooi ◽  
B. Qiu ◽  
...  
Keyword(s):  
Quantum Well ◽  
Laser Irradiation ◽  
Spatial Resolution ◽  
Point Defects ◽  
Pulse Length ◽  
Pulsed Laser ◽  
Double Quantum ◽  
Quantum Well Intermixing ◽  
Better Than ◽  
Pulsed Laser Irradiation

ABSTRACTAn essentially impurity free, direct write and potentially high spatial resolution quantum well intermixing technique using pulsed laser irradiation is reported. This technique uses a Q-switched Nd:YAG laser emitting at 1.06 μm with a pulse length of ∼20 ns and repetition rate of 10 Hz. The typical energy densities used for both Gain As/Gain AsP and GaAs/AlGaAs structures were ∼ 5 mJ mm−2. Multiphoton interactions with carriers lead to phonon emission, the phonons interact with the lattice thus generating point defects which diffuse during a subsequent annealing stage in a rapid thermal annealer and cause intermixing. Photoluminescence measurements have demonstrated that the spatial resolution of the process is better than the resolution of the PL measurement (ie better than 25 μm) and the technique has been used to write directly a grating of period 1.25 μm into a GalnAs/GalnAsP quantum well structure. This was achieved using a grating of period 2.5 μm etched into the surface of the substrate; when illuminated by the Q-switched pulses this grating generated a volume hologram of point defects within the sample at half the etched period. A clear dip in the transmission spectrum of the waveguide which had been processed in this way was observed at 1.525 μm. Differential bandgap shifts of up to 40 meV have been observed in GaAs/AlGaAs double quantum well samples. 3 μm wide ridge waveguide lasers were fabricated from the intermixed and control samples. The threshold currents of the intermixed and the control lasers were comparable. The slope efficiency of the intermixed lasers showed insignificant changes when compared to the as-grown lasers.

scholarly journals A real time high sensitivity high spatial resolution quantum well hall effect magnetovision camera

2017 ◽  
Vol 265 ◽  
pp. 127-137 ◽  
Author(s):  
Chen-Wei Liang ◽  
Ertan Balaban ◽  
Ehsan Ahmad ◽  
Zhichao Zhang ◽  
James Sexton ◽  
...  
Keyword(s):  
Quantum Well ◽  
Hall Effect ◽  
Real Time ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
High Sensitivity
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